The Hawaiʻi ʻelepaio was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

[2][3] Gmelin based his description on the "sandwich flycatcher" that had been described in 1783 by the English ornithologist John Latham in his book A General Synopsis of Birds.

[4] The specimen would have been collected between 17 January and 22 February 1779 near Kealakekua Bay on the island of Hawaii during James Cook's third voyage to the Pacific Ocean.

[5] The Hawaiʻi ʻelepaio is now placed in the genus Chasiempis that was introduced in 1847 by the German ornithologist Jean Cabanis.

[7] Three subspecies are recognised which differ in their ecological requirements and head coloration (see also Gloger's Rule):[6][8]